Yielding and plastic flow characteristics of a fine grained granular material

The serrated plastic flow of L12 Ni3 (Si,Ti) alloys at intermediate temperature was investigated by tensile tests in terms of the effects of temperature, strain rate, composition, and microstructure. Serrated plastic flow was most strongly observed at 473 K and at a strain rate of 1.6 × 10–4 s–1. Correspondingly, the maximum stress amplitude and the lowest (negative) strain-rate sensitivity were observed at 473 K. Serrated plastic flow took place irrespective of boron doping and was more significant in a fine-grained Ni3 (Si,Ti) alloy. The static aging at 473 K resulted in reduced flow stress. The activation energy for serrated plastic flow was estimated to be about 57 kJ mol–1, suggestive of being smaller than that for lattice diffusion of solutes. The serrated plastic flow behavior of Ni3 (Si,Ti) alloys was compared with that of L12 Co3Ti alloys, and is qualitatively explained on the basis of the dynamics of solutes in the core of a dissociated screw dislocation.

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Effect of cohesive interparticle force on the flow characteristics of granular material

Powder Technology ◽

10.1016/s0032-5910(02)00046-3 ◽

2002 ◽

Vol 126 (2) ◽

pp. 150-154 ◽

Cited By ~ 45

Author(s):

A.J Forsyth ◽

S Hutton ◽

M.J Rhodes

Keyword(s):

Granular Material ◽

Flow Characteristics ◽

Interparticle Force

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Effect of swaging on the 1000?C compressive slow plastic flow characteristics of the directionally solidified eutectic alloy ?/?'?-?

Journal of Materials Science ◽

10.1007/bf00547574 ◽

1983 ◽

Vol 18 (9) ◽

pp. 2581-2588 ◽

Cited By ~ 4

Author(s):

J. Daniel Whittenberger ◽

G. Wirth

Keyword(s):

Plastic Flow ◽

Eutectic Alloy ◽

Flow Characteristics ◽

Directionally Solidified

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The effect of strain rate on the plastic flow characteristics of steel and aluminium sheet

Journal of Strain Analysis ◽

10.1243/03093247v015439 ◽

1966 ◽

Vol 1 (5) ◽

pp. 439-446 ◽

Cited By ~ 10

Author(s):

A N Bramley ◽

P B Mellor

Keyword(s):

Strain Rate ◽

Uniaxial Tension ◽

Plastic Flow ◽

Work Hardening ◽

Sheet Steel ◽

Flow Characteristics ◽

Strain Rates ◽

Plastic Strains ◽

Aluminium Sheet

Work-hardening characteristics for sheet steel and aluminium have been obtained experimentally over a range of strain rates from 10−4 to 102/s. Use of the diaphragm test enables work-hardening characteristics to be obtained to much higher plastic strains than is possible in uniaxial tension. Results for killed steel show that the slope of the work-hardening characteristics decreases with increase in strain rate. Tentative extrapolation of the results suggests that if similar tests could be carried out at a strain rate of 104 then the work hardening characteristic would be that of an ideally plastic solid. In the case of aluminium the above phenomenon is not so marked and it is not possible to make even a tentative extrapolation to higher strain rates.

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